FALL RIVER — A Bristol County grand jury has indicted Carlos Ortiz and Ernest Wallace, two of Aaron Hernandez’s co-defendants, on murder charges stemming from the June 2013 homicide of Odin Lloyd.

Ortiz and Wallace were previously charged with accessory to murder after the fact, and both are already being held on $500,000 cash bail.

Both will be arraigned on the murder charges at a later date in Fall River Superior Court. The Bristol County District Attorney’s Office said it would have no comment on the indictments prior to the arraignment.

Ortiz’s lawyer, John J. Connors, said he was angry that he learned about Friday’s murder indictments from reporters. He said the district attorney’s office did not inform him ahead of time.

“They decided they were going to put out a press release and make this political, to the detriment of my client,” Connors said.

“It’s crazy. As far as I know, there is no new discovery as to why he would be charged with this,” Connors added. “If they were going to charge him based on whatever evidence they have, they should have charged him months ago instead of having him sit in jail believing he was there on a gun charge and then as an accessory after the fact.”

Wallace’s attorney, David Meier, did not return a phone call or email message seeking comment. Hernandez’s lawyers also did not return messages Friday.

The new murder indictments may be evidence of a new strategy by the district attorney’s office, which until now had decided to seek a murder indictment against only Hernandez, 24, the former Patriots star tight end.

“I’m surprised the prosecution didn’t charge Ortiz and Wallace from the very beginning with murder,” said Steven Sabra, a Somerset trial attorney and local legal analyst.

The indictments of Ortiz and Wallace, Sabra said, could mean prosecutors are pursuing a joint venture theory, in which co-defendants can be prosecuted if they know someone is going to commit a crime, if they share that person’s intent and are willing to assist in the offense. Sabra said the prosecution may have held out charging Ortiz and Wallace with murder in the hope that they would cooperate against Hernandez.

“This might mean that they are not cooperating,” Sabra said.

Prosecutors have said Hernandez orchestrated Lloyd’s murder in the North Attleborough Industrial Park after a disagreement the two men had a few nights earlier at a Boston nightclub.

Prosecutors said Hernandez called Ortiz, 27, and Wallace, 45, from Bristol, Conn., to meet him at his North Attleborough home on June 17, 2013. They then picked up Lloyd, 27, in Dorchester and drove to the industrial park.

Page 2 of 2 - A few minutes later, surveillance footage shows the three men leaving the industrial park without Lloyd, whose body was discovered the next morning, according to court documents.

Until a few months ago, it appeared that Ortiz would be the prosecution’s key witness against Hernandez. Ortiz told investigators after his arrest last June in Connecticut that Wallace and Hernandez exited the vehicle with Lloyd in the industrial park. He also recounted conversations between Hernandez and Lloyd in the vehicle, told police that he saw Hernandez carrying a handgun and made apparent references to Hernandez’s alleged “flophouse” in Franklin, which “other football players used” and where investigators said they found evidence, including clothing and ammunition, according to court documents.

However, Ortiz later changed his story to say Hernandez was alone with Lloyd outside the vehicle. Court records indicate that Ortiz made a preliminary offer to cooperate with prosecutors but that they ultimately decided not to call him to the witness stand because they saw him as too unreliable.

In a previous court filing for discovery, Hernandez’s defense team also requested information about police telling Ortiz last June that his hair and DNA were found on a white towel that investigators located near Lloyd’s body in the industrial park.

A bill of particulars filed last month also alleges that Ortiz helped Hernandez and Wallace escape arrest “through flight from the scene” and that he took possession of a firearm that was not the murder weapon. Prosecutors also allege that Ortiz lied to police, disposed of his phone and clothing and helped Hernandez return the rental vehicle used in Lloyd’s murder.

Connors disputed that account, saying that Ortiz went along for a ride with a friend he admired and that he got caught up in the “wrong place at the wrong time.”

Connors also hinted at the possibility that he may have to recuse himself from the case because of “some of the things (law enforcement) made (Ortiz) do.

“I may end up being called as a witness,” said Connors, who declined to elaborate when pressed.